wounds

You might have brushed by it in the forest, where this hairy-looking symbiosis between algea and fungi perches on tree limbs. The look of the lichen usnea explains its nicknames: "old man's beard," "tree's dandruff," "women's long hair," and "beard lichen." For centuries, it's been considered a handy medicinal. People grab some to dress wounds, or take it internally for infections or oral inflammation. But in the 1990s, when manufacturers of weight-loss drugs started adding sodium usniate (usnic acid) to their formulas, several cases of liver damage emerged.

In 1905, author Harriet Keeler wrote about the inner bark of the slippery elm tree: “It is thick, fragrant, mucilaginous, demulcent, and nutritious. The water in which the bark has been soaked is a grateful drink for one suffering from affections of the throat and lungs.”

December 28th & 30th, 2013:Prized as incense, myrrh plays a role in the ceremonies of many religions, but also in medicine. Its antimicrobial qualities have made it useful for treating wounds, infection, inflammation, and candida - and today, it's found in toothpastes.

December 21st & 23rd, 2013:For millenia throughout the Arabian Peninsula and North Africa, resinous nuggets from the frankincense tree have made fragrant and insecticidal smoke when burned. Frankincense is considered sacred as well as medicinal, but today, the trees aren't reproducing.